Inertia responsive latch mechanisms for vehicle seats are well known in the prior art. For example, the U.S. Pat. Nos. 4,318,569 to Bilenchi et al issued Mar. 9, 1982, and the U.S. Pat. No. 4,438,974 to Kresky et al issued Mar. 27, 1984, disclose such inertia responsive latch mechanisms. The '569 and '974 patent disclose seat back latch mechanism comprising a latch pall which is pivotally mounted on a seat back frame and arranged so that gravity will cause the pall to swing out of latching attitude when a force is applied to the seat back at less than a predetermined acceleration. When a predetermined acceleration of the seat back has been reached, the latch pall engages a shoulder and prevents forward tilting of the seat.
The aforementioned members employ a single inertia latch element which is maintained in a cam-controlled latching attitude relative to a fixed detent or shoulder. The inertia latch element will engage the detent or shoulder when a predetermined acceleration of the seat back has been reached. If this predetermined acceleration is not reached, gravity will cause the inertia element to rotate out of latching attitude with the detent or shoulder, thus allowing the seat to move to the forward position.
None of the known inertia latch assemblies show the feature of locking the seat in the forward position by the inertia latch element until manually released.